136 



SCIENCE. 



[N. S. Vol. XXIII. No. 578. 



now easily obtained, partly by the addition of 

 one hundred and fifty pages to the book. The 

 larger part of the new experiments pertain to 

 electrochemistry, but there have been included, 

 also, experiments with liquid air, Gold- 

 schmidt's process for obtaining high tempera- 

 tures and a considerable number of experi- 

 ments to illustrate the principles of the newer 

 physical chemistry. One finds, also, experi- 

 ments with hydroxylamine, hyrazine, hydrazoic 

 acid and with fiuorine. The new experiments 

 as well as the old are, in general, well selected 

 and clearly described. Only occasionally is an 

 error to be noted, as where the decomposition 

 of ammonia gas by electric sparks is spoken of 

 as an electrolysis. Every one who has occa- 

 sion to give experimentally illustrated lectures 

 in chemistry will find in the book a storehouse 

 of valuable material. W. A. N. 



A Treatise on Chemistry. By Sir H. E. 

 EoscoE and C. Schorlemmer. Vol. I., The 

 Non-metallic Elements. New edition com- 

 pletely revised by Sir H. E. Eoscoe assisted 

 by Drs. H. G. Coleman and A. Harden. 

 London, Maemillan & Co., Ltd. ; New York, 

 The Maemillan Co. Pp. xii -f 931. 

 This book has been so well and so favorably 

 known since its first appearance more than 

 twenty-five years ago that an extended notice 

 is not necessary. Those features which made 

 the first edition such delightful reading have 

 been retained, while, at the same time, the au- 

 thors have incoi-porated with painstaking care 

 the results of a very large amount of experi- 

 mental work which has enriched our science 

 during the past quarter of a century. The 

 completeness and accuracy with which this' 

 has been done are really surprising. 



A rather brief discussion of the properties 

 of solutions from the modern point of view 

 is given, but in matter pertaining to the newer 

 physical chemistry the book can not be con- 

 sidered as altogether satisfactory. The omis- 

 sion of the chapter on crystallography is to 

 be regretted. It also seems unfortunate that 

 the double standard for atomic weights should 

 be used at a time when chemists seem to have 

 decided pretty generally in favor of a single 

 standard. 



A very good though rather brief account of 

 the gases of the helium group is given. 



W. A. N. - 



Cours de Chimie. A L'Usage des Etudiants 

 du P. 0. N. Par E. de Eorchand. Paris, 

 Gautier-Villars. 1905. Vol. I., 325 pp.; 

 Vol. II., 317 pp. Price, 10 francs. 

 These books, according to the author's state- 

 ment, are intended for the use of students who 

 are intermediate in attainment between those 

 who are candidates for the bachelor's degree 

 and for the degree of master of arts. They 

 are intended to furnish the basis for three 

 exercises a week for one year. The plan fol- 

 lowed is that of presenting an outline of the 

 more important theories of chemistry first be- 

 fore considering any details with regard to the 

 elements or their compounds — a method which 

 may answer for students who have already 

 acquired a considerable knowledge of the sub- 

 ject, but one which is wholly unsuitable for 

 beginners. The theoretical point of view of 

 the book corresponds more nearly to that of 

 the average chemist fifteen years ago than to 

 the present condition of the science. One is 

 surprised to find the long-abandoned ' principle 

 of maximum work' presented as one of the 

 fundamental principles of chemistry; also the 

 old formula Cl-0-O-OH for chloric acid. The 

 portions devoted to organic and to analytical 

 chemistry are so brief as to be quite unsatis- 

 factory. In the former many structural for- 

 mulae are given, but no attempt is made to 

 give the student an idea of the means by 

 which such formulse are developed. 



By an oversight the author has retained the 

 old value for the density of hydrogen. Less 

 excusable is the value 15.84 for the atomic 

 weight of oxygen on the hydrogen basis, cal- 

 culated from the value 1.01 for hydrogen, as 

 given by the international committee, and that 

 too with the statement that the ratio is very 

 accurately known. 



The volumes contain no index. 



W. A. N. 



strabo on climatology. 

 Klimalehre der alien Oriechen nach den Geo- 

 graphica Strahos. Von Dr. Hans Eid. 

 Kaiserlautern, 1904. 8vo. Pp. 62. 



